CVE-2026-55964

Chain intermediate CA:TRUE without keyCertSign accepted as a signing CA. Intermediate CA certificates are required to have the keyCertSign key usage when a Key Usage extension is present, but chain-supplied temporary CAs (WOLFSSLTEMPCA) added while building a certificate path were previously exempted from this check, so an intermediate asserting CA:TRUE but lacking keyCertSign was accepted as a signing CA. The check now applies to chain-supplied temporary CAs as well; only operator-loaded root certificates (WOLFSSLUSERCA) and self-signed roots remain exempt. Per RFC 5280 an absent Key Usage extension implies all usages, so the requirement is enforced only when the extension is actually present (extKeyUsageSet). Affects the OpenSSL-compatibility certificate-path-building path (X509verifycert / X509STORE, OPENSSLEXTRA/OPENSSLALL), where untrusted chain intermediates are added as temporary CAs; native (non-OpenSSL-compat) certificate verification does not create temporary CAs and is unaffected. Within those builds, the check applies unless ALLOWINVALID_CERTSIGN is defined.

Database specific

{
    "cwe_ids": [
        "CWE-295"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55964.json",
    "cna_assigner": "wolfSSL"
}

References

Affected packages

Git / github.com/wolfssl/wolfssl

Affected ranges

Type

GIT

Repo

https://github.com/wolfssl/wolfssl

Events

Introduced

bdd62314f00fca0e216bf8c963c8eeff6327e0cb

Fixed

ac01707f552c611fbd135cc723b2682b3e7f80f2

Database specific

{
    "cpe": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "5.7.4"
        },
        {
            "last_affected": "5.9.1"
        },
        {
            "fixed": "5.9.2"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "CPE_RANGE"
    ]
}

Affected versions

v5.*

v5.2.1

v5.7.4-stable

v5.7.6-stable

v5.8.0-stable

v5.8.2-stable

v5.8.4-stable

v5.9.0-stable

v5.9.1-stable

Other

wolfEntropy2d

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55964.json"